Reform of the “fitness for work” assessment of sick and disabled people has been too slow and the system is still causing “considerable disquiet”, the third independent review of the system has said.

Professor Malcolm Harrington criticised the French healthcare firm Atos which carries out the face-to-face assessments and questioned whether the company had done all it could to improve the process for vulnerable claimants.

In his review, Professor Harrington concluded that improvements to the tests had been disappointingly slow. His inquiry had been inundated with evidence from claimants who told him of their distressing experiences when attending the face-to-face assessment.

Despite improvements, “considerable disquiet remains,” he concluded. “Claims of rude healthcare professionals, often more focused on the computer screen than the individual, remain frequent,” he said.

An Atos spokesman said: “We will work with the DWP to consider all the recommendations in order to further improve our service.”

The minister for Employment, Mark Hoban, said: “The changes we have made already to make the work capability assessment more accurate mean the proportion of people being placed in the support group for employment support allowance has more than doubled in two years.”